Symfony2 FOSUserBundle corrupted CSS when redirecting with access_control

I use FOSUserBundle with Symfony. When I use this in access_control: - { path: ^/, role: ROLE_USER } my CSS is not entirely well displayed. I have 2 calls to my CSS in my layout.html.twig:

{% set bootstrap_style = client.styles.front.stylesheet %}
<link rel="stylesheet" href="{{ asset('bundles/portalfront/css/bootstrap.' ~ bootstrap_style ~ '.css' ) }}" />

Then I have :

{% stylesheets filter="cssrewrite"
    'bundles/portalfront/css/font-awesome.min.css'
    'bundles/portalfront/css/style.css'
%}
<link rel="stylesheet" href="{{ asset_url }}" />
{% endstylesheets %}

This second call seems to be corrupted when I use - { path: ^/, role: ROLE_USER } but works very fine if I use - { path: ^/$, role: ROLE_USER } Here is my security.yml :

security:
    providers:
        fos_userbundle:
            id: fos_user.user_provider.username_email

    encoders:
        FOS\UserBundle\Model\UserInterface: sha512

    firewalls:
        main:
            pattern: ^/
            form_login:
                provider: fos_userbundle
                csrf_provider: form.csrf_provider
            logout:       true
            anonymous:    true

    access_control:
        - { path: ^/login$, role: IS_AUTHENTICATED_ANONYMOUSLY }
        - { path: ^/register, role: IS_AUTHENTICATED_ANONYMOUSLY }
        - { path: ^/resetting, role: IS_AUTHENTICATED_ANONYMOUSLY }
        - { path: ^/admin/, role: ROLE_ADMIN }
        - { path: ^/, role: ROLE_USER }

    role_hierarchy:
        ROLE_ADMIN:       ROLE_USER
        ROLE_SUPER_ADMIN: ROLE_ADMIN

When I say it's corrupted, I mean all the styles are not applied and when I inspect the files in chrome debug I see html code instead of CSS code in my .css file. And another thing disturbing is that my bootstrap style which is well applied, seems to be called many times. Maybe we have here a sort of redirecting which corrupt the CSS files not entirely loaded.

NOTE: I have this problem ONLY in DEV mode, absolutely no problem in Production.

I found the solution here :

https://github.com/FriendsOfSymfony/FOSUserBundle/issues/368

The problem is that you have to disable route of debug toolbar in your firewall like this :

// security.yml
firewalls:
    dev:
        pattern:  ^/(_(profiler|wdt)|css|images|js)/
        security: false

Be sure to add dev firewal BEFORE main firewall.